This present invention relates to the field of audio/video playback devices and in particular, to a playback device that supports playing back data that is encoded in more than one format.
A playback apparatus receives from a data source that delivers audio and/or video data. The data source may be of very different nature; for example, it may be hidden behind a data interface if the data are received from the Internet or another data network via a personal computer (PC). Other examples of such data sources are compact data storage in which the data are stored (e.g., magnetically, optically, electronically, or on another principle) and converted during readout into an electronic data stream by suitable devices. Also suitable for use as compact data sources are solid-state memories, because such memories do not require a mechanical drive.
Data from the data source is converted to an error corrected data stream, and fed to an output decoder that separates the data stream into the respective signal components and, if necessary, converts the latter from digital to analog form. These signal components are then fed to a playback transducer (e.g., headphones, loudspeakers, etc.). In the case of video signals, the playback transducer may be a television receiver, a multimedia apparatus, or a simple video display on the playback apparatus.
CDs are reasonably priced devices for storing audio data, and have the benefit of being rewriteable (i.e., CD-RW). The original data is frequently streamed from the Internet. To permit the use of commercially available audio playback apparatus, the data must be stored according to submitted standards, for example according to the “Sony-Philips Red/Blue Book”.
The transmission, storage, and reproduction of data, particularly of audio data, in accordance with these standardized data formats is very common. However, it has the disadvantage that these standardized data formats frequently do not provide for data compression or only provide for relatively little data compression, so that they do not make optimum use of the existing storage space. On the other hand, there are techniques in which the level of compression can be chosen in a wide range. Pure voice applications allow a higher compression level than high-quality music reproduction. Such compression and coding techniques are known, for example, by the acronym “MPEG”, and are used, for example, in the optical storage of video and audio signals for a DVD system. It is desirable to take advantage of these data compression techniques, while retaining the proven recording, storage, and playback system as far as possible. In particular, a playback apparatus is desirable that is suitable for the reproduction of at least one improved data format and conventional or mixed data formats.